It has been reported in Patent Document 1 that a 5-membered ring compound inhibits a late asthmatic response, but no disclosure has been found about an agent for preventing and/or treating COPD which are different from asthma in mechanism of activity and utility.
A chronic obstructive pulmonary disease had been defined as a disease characterized by airflow obstruction (obstructive ventilatory impairment) caused by chronic bronchitis, lung emphysema or a complication thereof, but has been defined as “a disease state characterized by airflow limitation that is not fully reversible. The airflow limitation is usually both progressive and associated with an abnormal inflammatory response of the lungs to noxious particles or gases” in the international guideline GOLD (Global initiative for Chronic Obstructive Lung Disease) published in April, 2001. COPD is also referred to as “a chronic nonspecific lung disease which is manifested an obstructive ventilatory impairment due to lung emphysema or small airway disease caused by harmful gas or particles of cigarette.” Cigarette smoking history is important in terms of clinical history. Cigarette smoking is a clear cause of COPD, and an obstructive ventilatory impairment progresses to a chronic progressive disease due to cigarette smoking. Any other causes of COPD include air pollution and occupation (occupation which breathes the fumes, for example a chef), and a promoting factor includes infection. COPD is a progressive irreversible chronic disease, and most part of causes thereof is cigarette smoking. Accordingly, treatment which delays a progression of the disease is smoking cessation, and treatment which significantly contributes to a prognostic improvement after respiratory failure (PaO2 60 mmHg and below) is a domiciliary oxygen therapy.
It has been reported that neutrophil numbers and concentrations of TNF-α and IL-8 rise by analysis of bronchoalveolar fluid in COPD patients (Non-patent Document 1). Also, it has been suggested by analysis of COPD patients or animal model of disease that an anti TNF-α therapy can be effective for treatment of COPD and inhibition of progression (Non-patent Document 2). Accordingly, an agent effective for treating and/or preventing COPD may be such drugs that inhibit depressed production of IL-8, infiltration/activation of neutrophil, depressed production of TNF-α, infiltration/activation of alveolar macrophage which is one of inflammatory cells which produce IL-8 or TNF-α, thickening of airway epithelium or alveolar wall, or a responsible factor thereof, and further, emphysematous lesion including destruction of alveolar wall or a responsible factor thereof.    Patent Document 1: WO 02/02542    Non-patent Document 1: Am. J. Respir. Crit. Care Med. 153, 530-534 (1996)    Non-patent Document 2: New Drugs for Asthma, Allergy and COPD., Prog. Respir. Res., Basel, Karger, 31, 247-250 (2001)